2 Answers
2

first of all why do you use sudo command before rvm? this link will help you in that rvm.io/rubies/rubygems . I don't thing that you have to use sudo.
Also you can look into this question error while installing ruby 1.9.3 using rvm
Also 'rvm install ruby' will install you latest stable version of ruby.

You are using an very old version of RVM that is packaged with Ubuntu, make sure to follow instructions from this answer http://stackoverflow.com/a/9056395/497756 - gunzip is no more used in RVM so this problem should be fixed.

i have follow the instructions to install rvm, but when i try to run this -> rvm requirements the terminal show this: The program 'rvm' is not currently installed. You can install it by typing: sudo apt-get install ruby-rvm
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Arthur MorenoJan 12 '13 at 12:13